Apparatus for initiating operation of a combined drawing and texturing machine for yarn

ABSTRACT

A machine which combines drawing and texturing operations is equipped with a yarn launching device with which the yarn is initially wrapped partially around a heating element before the yarn is drawn and textured. This is accomplished by a curved bar which has yarn engaging members at opposite ends thereof and which pivots over the heating element to wrap the yarn partially therearound. An arm projects from the curved bar and also has a yarn engaging member thereon which deflects the yarn upstream of the heating element away from the heating element. After the drawing and texturing operations are commenced, the curved bar and arm are returned to a rest position to release the yarn from engagement with the heating element.

United States Patent Crouzet et al. Sept. 9, 1975 [54] APPARATUS FOR INITIATING OPERATION 3,733,801 5/1973 Jones 4. 57/157 T8 or A COMBINED DRAWING AND 21:33: 32'? r r t 3x2 ringer TEXTURING MACHINE FOR YARN 3,796,036 3/l974 Parker 57/l57 TS [75] Inventors: Henri Crouzet, Renaison;

Jean-Claude Dupeuble Roanne Primary ExaminerDonald E. Watkins both of France Attorney, Agent, or FirmSherman & Shalloway [73] Assignee: Ateliers Roannais de Constructions Textiles soclete, Roanne, France ABSTRACT 4, l 7 [22] Filed Jan 9 4 A machine whlch combines drawing and texturmg op- [21] Appl. No.: 430,791 erations is equipped with a yarn launching device with which the yarn is initially wrapped partially around a heating element before the yarn is drawn and text P [30] Foreign Apphca nonty Data tured. This Is accomplished by a curved bar which has l973 France 7303117 yarn engaging members at opposite ends thereof and which pivots over the heating element to wrap the [52] US. Cl 57/34 HS; 57/106, 57/157 TS yam partially thereamund. An m projects from the [51] Int. Cl. D02g 1/02 Curvad bar and also has a yam engaging membe'r [58] held of Search" 57/34 34 157 TS thereon which deflects the yarn upstream of the heating element away from the heating element. After the [56] References cued drawing and texturing operations are commenced, the UNITED STATES PATENTS curved bar and arm are returned to a rest position to 3,166,822 1/1965 Starkie 57/34 HS X release the yarn from engagement with the heating el- 3,443 37l 5/1969 Ward 57/34 HS ement, 3,638,4ll 2/l972 Tsugawa et a]. 57/34 HS 3,729,916 5/1973 Lusk 57/34 HS 8 Claims, 4 Drawing Figures PATENTEDSEP 9197s 3 903 682 Sam 1 1F 2 APPARATUS FOR INITIATING OPERATION OF A COMBINED DRAWING AND TEXTURING MACHINE FOR YARN BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to combined drawing and texturing machines. More particularly, the present invention relates to drawing and texturing machines in which drawing and false twist texturing of thermoplastic synthetic yarns are performed in a combined manner and preferably simultaneously.

2. Technical Considerations and Prior Art It is known that in order to produce a synthetic yarn having improved bulk and/or extensibility, the yarn may be subjected to a texturing treatment by false twist during which the yarn continuously undergoes the operations of twisting, setting, untwisting and finally resetting.

It has been proposed to combine this treatment with the well known drawing treatment which consists of stretching the filaments at their exit from the extrusion spinnerette by several times their length so as to orient the molecular chains of which they are composed.

For performing this process, it is possible to use either filaments which have received no functional stretch other than the spinning stretch (undrawn filaments) or filaments which have already received a substantial stretch (partly drawn yarn) and which are still capable of receiving a certain amount of irreversible plastic elongation.

In the description which follows, the expressions undrawn filaments or partly drawn yarn" will be used interchangeably since the drawing and texturing process can be indiscriminately applied in its general concept to either of these yam forms.

In spite of the advantages of combining the drawing and texturing processes, there are a number of practical problems that are not overcome by the prior art. It is known that undrawn polyester filaments have a great tendency to crystallize under the influence of heat and thereby become fragile. Thus, during the course of launching or starting the contemplated drawing and texturing process, it is essential for the undrawn filament not to be placed in contact with a heating element in its original condition. This consideration makes it impossible to start machines in which the yarn is passed through disengaged elements and then engaged with the elements in order to process the yarn. This is especially the case where the machines comprise a closed texturing oven as, for example, in the well known and widely used machine such as that described in US. Pat. No. 2,891,375.

In order to obviate these drawbacks, it has been proposed to use open ovens against which the yarn will be laid only after termination of the starting operation. Unfortunately, it is known that in false twist texturing, the use of open ovens results in textured yarns which often lack, among other things, adequate bulk and tinctorial affinity, and which require high consumption of electric energy. Furthermore, it is also known that when an undrawn (or partly drawn) filament is introduced into the twist locking means of the false twist spindle, accumulations, partial and irregular drawings result due to the thickness count of the yarn. This fre quently causes the yarn to rupture.

Thus, in order to obtain satisfactory products, it is important, on the one hand, to use closed texturing 0v ens, and on the other hand, to supply to the spindle an initially stretched yarn at the time of start up. The prior art solutions are incompatible with these two essential conditions. Consequently, the development of these drawing and texturing techniques has not met with anticipated success.

SUMMARY OF THE INVENTION It is therefor an object of the present invention to provide new and improved methods of and apparatus for rendering closed ovens compatible with a yarn treatment process in which drawing and texturing by false twist are coordinated with launching the yarn.

It is another object of the present invention to provide new and improved methods of and apparatus for initiating operation of combined drawing and texturing machines wherein yarn is substantially stretched over a heating element upon launching the yarn and then is removed from the heating element after launching.

It is still another object of the present invention to provide new and improved methods of and apparatus for combining drawing and texturing operations for yarn, wherein a heating element is situated upstream of the site of the texturing operation and wherein the yarn is initially stretched over the heating element and then released.

Accordingly, to practice this invention, one apparatus for drawing synthetic plastic yarns and texturing the yarn by false twist includes means for combining the steps of drawing and texturing. The apparatus utilized comprises means for supplying the synthetic yarn to be drawn and textured, a twist-setting member, a heating assembly positioned upstream of the above member and movable to an out-of-the-way position, a yarn feeder situated upstream of the heated twist setting member, a false twist spindle, a yarn feeder situated downstream of the spindle, and elements for winding up the so produced textured yarn.

Preferably, the heating assembly includes a heating element and a curved bar capable of at least partially surrounding the heating element. The curved bar is pivoted at one of its ends about an axis which is substantially parallel to the principal axis of the heating element and carries yarn deflecting elements at both ends. An arm connected by one of its ends to the fulcrum of the bar carries a yarn deflecting element at its free end and has a clever portion which is also joined to the curved bar in the vicinity of its fulcrum. When the lever is lifted, it causes the assembly to pivot about the heating element.

The heating element may be formed of a metallic cylinder or drawing finger which is heated by any suitable means, such as electricity or hot liquid, while the twist setting member may consist of an electrically heated, curved tube.

The deflecting means situated at the appropriate ends of the bar may utilize stationary diabolo-shaped yarn guides which are elements well known per se in the textile industry. Fixed diabolo-shaped yarn guides of ceramic material are conveniently employed.

It has been found that improved results are obtained when at least one additional deflecting means, which acts as pre-tensioning means, is placed upstream of the heating assembly according to the invention.

This invention is particularly suitable for machines intended simultaneously to perform the drawing and texturing steps.

BRIEF DESCRIPTION OF THE DRAWINGS In order that the invention will be more fully understood, the following description is given merely by way of example, reference being made to the accompanying drawings, in which:

FIG. 1 shows one embodiment of apparatus according to this invention in its normal position; i.e., prior to strat up in normal running of the drawing and texturing frame;

FIG. 2 schematically shows the apparatus according to the invention of FIG. 1 in the start up or launching position; and

FIGS. 3 and 4 are views similar to FIGS. 1 and 2 of a second embodiment.

DETAILED DESCRIPTION A polyester yarn 1 having a residual draw ratio of 3.5 is unwound from a yarn package (not shown), passes through a dish-type tensioning means 2, then under a texturing floor, and thereafter enters the apparatus according to the invention.

This apparatus includes a draw finger 3 in the form of a cylinder of, for example, 60 mm outside diameter, heated by electricity. A curved bar 4, optionally of metal, is pivotable about its end carrying a yarn guide 5 about an axis which is parallel to the axis of the draw finger 3. Carried at each end of the curved bar 4 are fixed diabolo-shaped yarn guides 5 and 6 made of ceramic material and having inner necks with a diameter of IO mm. The curvature of the bar 4 substantially is such as to wrap around the draw finger 3 and the length of the bar 4 is such that the yarn 1 passing under the yarn guides 5 and 6 is in contact with the finger over an angle of about 180.

An arm 7 connected to the bar 4 at the position of yarn guide 5 carries at its free end a fixed diaboloshaped yarn guide 8 of the same shape and nature as yarn guides 5 and 6.

A lever 9 is joined both to the bar 4 and the arm 7 at the pivot point 5. The lever 9 has suitable means associated therewith, such as springs, notches, etc., to permit it to pass from the FIG. 1 position to the FIG. 2 position and to remain arrested in either position.

Further yarn deflecting means in the form of a fixed diabolo-shaped yarn guide 10 is located upstream of this assembly. The axis of the yarn guide 10 is parallel to and situated in the same plane as the fulcrum 5 and the draw finger 3. All of the axes of the yarn guides 5, 6, 8 and 10 are substantially parallel.

The texturing frame includes a first yarn feeder 11, which may utilize a belt 16 which holds the yarn in engagement with a roller 17. From the yarn feeder 11, the yarn advances through a texturing furnace or heating member 12 consisting of an electrically heated, curved tube having a length of one meter. Downstream of the furnace 12 is a conventional false twist spindle l3, and a second yarn feeder 14 which is similar to the feeder 11. However, the feeder 14 is gradually positioned, such as the one which is, for example, described in U.S. Pat. No. 3,831,830, on a Yam Feeding Device for Textile Machines." Further upstream there is a second furnace, a further array of delivery rollers and finally yarn wind-up means, all of which are well known per se and are not shown.

In order to start the machine, one proceeds in the following manner. The yarn I passes through the tensioning means 2, then under bar 10, over guide 8, under guide 5 and finally under guide 6 (see FIG. 1). The lever 9 is then raised (see FIG. 2) so that the yarn 1 contacts the heating element or finger 3 over about In this way, the yarn l is substantially stretched over the heating element or finger 3.

The yarn is next passed into the disengaged feeder 1 1, into the furnace 12, through the disengaged spindle l3 and finally into the feeder 14 which is held in slipping" condition; i.e., is not entirely engaged. The yarn, which is now introduced into the furnace 12, has been virtually drawn and has no tendency to crystallize. Therefore, the yarn will not break, thus making the launching operation possible. In a manner know per se, the yarn l is next passed manually through all of the other successive elements of the machine; i.e., the feeders and second furnace, etc. The yarn is then recovered at a waste suction nozzle.

When the start up or launching operation is completed, the feeder 11 is engaged and the lever 9 is depressed so that the yarn l is no longer in contact with the heating element or, rather, the finger 3. The feeder l4 and the spindle 13 are then engaged and finally the textured yarn is subsequently wound on a receiving bobbin (not shown).

In another solution, the lever 9 and the feeder 16 can be tied together, so that the engagement of the feeder 16 provides the opening of the lever 9.

The method according to the invention consists of utilizing a heating assembly situated upstream of the furnace for launching the yarn. The assembly is then, in effect, disengaged from the yarn after the launching operation has been performed. Thus, the apparatus according to the invention enables concurrently phased drawing/texturing frames equipped with closed furnaces to be started conveniently and therefor to produce yarns of better textile quality, improved uniformity, extensibility and dying affinity.

Since the operation of lowering the yarn 1 onto the finger 3 with the pre-tensioning means (rollers 5, 8 and 10) is effected progressively, the yarn entering the furnace is stretched progressively less, which avoids jolts and hence facilitates the launching operation. Finally, since the lever 9 can comfortably be foot-controlled, the operator can concentrate all of his attention on manipulations of the yarn in the spindle 13 and on positioning of the feeder 14. It has been observed that when working in this manner the launching operation is carried out in a very brief period of time which presents a considerable advance over other closed furnace approaches and results in appreciable economies.

FIGS. 3 and 4 are views similar to FIGS. 1 and 2 and show a modified form of apparatus in which similar parts are identified with like reference numerals. In this construction, the first yarn feeder l l is placed immediately adjacent the tensioning means 2, so that the heating assembly comprising the members 3 10 is located downstream of the yarn feeder l l, but still upstream of the heating member 12.

Although the embodiment of the afore-described invention is used with simultaneous drawing and texturing machines, it is clear that if it is so desired, the invention may be practiced continuously with the combined drawing and texturing method or in separate steps. Accordingly, a frame equipped with this apparatus could be used for drawing and texturing either in separate stages or simultaneously. This increases appreciably the versatility of the frames to a substantial degree.

What is claimed is:

1. An apparatus for drawing and texturing synthetic thermoplastic yarn by false twisting the yarn, wherein the drawing and texturing are performed simultaneously and wherein the apparatus includes means for supplying the synthetic yarn, a heated twist-setting member for setting a twist in the yarn, a heating assembly upstream of the heated twist-setting member, a false twist spindle, a yarn feeder situated downstream of the spindle and means for winding up the resulting textured yarn; the improvement in which said heating assembly comprises:

a heating element;

a curved bar positioned and configured to partially surround the heating element;

means for mounting the curved bar to pivot about one end so as to overlie said heating element; means for engaging and deflecting the yarn, disposed in spaced relation on said bar to accommodate the heating element therebetween when said curved bar overlies said heating element to thereby hold the yarn in engagement with said heating element; arm means connected to said curved bar means at the pivoted edge of said curved bar means, said arm means having means thereon for engaging and deflecting the yarn away from the heating element upon pivoting the curved bar; and

means associated with said curved bar and said arm means for moving said curved bar and said arm means to pivot and carry the yarn into and out of engagement with the heating element.

2. An apparatus according to claim 1, wherein the heating element comprises a heated metallic cylinder.

3. An apparatus according to claim 1 wherein the engaging and deflecting means bring the yarn into contact with the heating element over a substantial arc.

4. An apparatus according to claim 1, wherein the deflecting elements comprise diabolo-shaped yarn guides.

5. An apparatus according to claim 4, wherein the diabolo-shaped yarn guides are stationary.

6. An apparatus according to claim 1, wherein the heating element is situated upstream of the yarn feeder which is situated upstream of the heated twist-setting member.

7. An apparatus according to claim 1, wherein the heating element is situated between the heated twistsetting member and the yarn feeder which is situated upstream of the heated twist-setting member.

8. An apparatus according to claim 6, wherein the arm is connected to the yarn feeder which is situated upstream of the heated twist-setting member. 

1. An apparatus for drawing and texturing synthetic thermoplastic yarn by false twisting the yarn, wherein the drawing and texturing are performed simultaneously and wherein the apparatus includes means for supplying the synthetic yarn, a heated twist-setting member for setting a twist in the yarn, a heating assembly upstream of the heated twist-setting member, a false twist spindle, a yarn feeder situated downstream of the spindle and means for winding up the resulting textured yarn; the improvement in which said heating assembly comprises: a heating element; a curved bar positioned and configured to partially surround the heating element; means for mounting the curved bar to pivot about one end so as to overlie said heating element; means for engaging and deflecting the yarn, disposed in spaced relation on said bar to accommodate the heating element therebetween when said curved bar overlies said heating element to thereby hold the yarn in engagement with said heating element; arm means connected to said curved bar means at the pivoted edge of said curved bar means, said arm means having means thereon for engaging and deflecting the yarn away from the heating element upon pivoting the curved bar; and means associated with said curved bar and said arm means for moving said curved bar and said arm means to pivot and carry the yarn into and out of engagement with the heating element.
 2. An apparatus according to claim 1, wherein the heating element comprises a heated metallic cylinder.
 3. An apparatus according to claim 1 wherein the engaging and deflecting means bring the yarn into contact with the heating element over a substantial arc.
 4. An apparatus according to claim 1, wherein the deflecting elements comprise diabolo-shaped yarn guides.
 5. An apparatus according to claim 4, wherein the diabolo-shaped yarn guides are stationary.
 6. An apparatus according to claim 1, wherein the heating element is situated upstream of the yarn feeder which is situated upstream of the heated twist-setting member.
 7. An apparatus according to claim 1, wherein the heating element is situated between the heated twist-setting member and the yarn feeder which is situated upstream of the heated twist-setting member.
 8. An apparatus according to claim 6, wherein the arm is connected to the yarn feeder which is situated upstream of the heated twist-setting member. 